通过镜组移动改变正、负傅里叶变换系统的距离，用软件比较CCD上两个波峰的间隔是否变化来对CCD进行定焦。

When the distance between positive and inverse Fourier transform system changes, the CCD is adjusted to the focal plane by variable value of interval between two peaks on CCD with computer.

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此款定焦式的望远镜没有个性化的目镜曲光镜调节。

This binocular is of fixed-focus type and has to be used with eye-glasses by anybody with visual defects.

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